Mariner, Viking & MGS's Maps & Mars in the '70s
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N-Mariner7-09_enn_21.jpgMars from Mariner 7: Craters and Ridges53 visitenessun commento
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O-Mariner9-00.jpgMars from Mariner 9: Canyons, troughs and cracks53 visitenessun commento
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O-Mariner9-01.jpgMars from Mariner 9: Craterland...57 visitenessun commento
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O-Mariner9-02.jpgMars from Mariner 9: Olympus, alias Nix Olimpica53 visitenessun commento
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O-Mariner9-03.jpgMars from Mariner 9: Collapsed terrain53 visitenessun commento
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O-Mariner9-04.jpgMars from Mariner 9: the North Pole of Mars53 visitenessun commento
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O-Mariner9-71-PIA02989_modest.jpgSouth Polar Cap from Mariner 9 and 7127 visiteCaption NASA originale:"This mosaic of Mariner 9 frames (top), taken during the first orbit, shows the remnants of the South Polar Cap of Mars dimly through the great dust storm. Mariner 7 photographed the same area in August, 1969 (bottom) at which time the entire region was covered with dry ice. The strange quasilinear features of 1969 have been replaced by a number of bright curved appendages never before seen on Mars and, at this time, unexplained. Mariner 9 was the 1st spacecraft to orbit another planet. The spacecraft was designed to continue the atmospheric studies - begun by Mariners 6 and 7 - and to map over 70% of the Martian surface from the lowest altitude (1500 Km [approx. 900 miles]) and at the highest resolutions (1 Km per pixel to 100 meters per pixel) of any previous Mars mission".
Eccezionale, semplicemente: Mariner 9 venne lanciato il 30 Maggio 1971 ed arrivò a destinazione il 14 Novembre dello stesso anno.
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O-Mariner9-71-PIA02998_modest.jpgMars from Mariner 9: Canyon System emerging from Martian Dust Storms123 visiteOggi, come sapete, le Missioni "Mars Rovers" vengono - sia pure solo "a singhiozzo"... - celebrate ogniqualvolta i "robottini" si imbattono in qualcosa di "interessante e/o curioso", a detta degli Operatori del Centro Controllo Missione. Ogni risultato ottenuto dalla NASA (o dall'ESA, ancorchè in misura minore), oggi, viene - quantomeno inizialmente - celebrato come un autentico "Trionfo della Scienza e della Tecnologia". Un Trionfo del "Sapere Umano", insomma. Ma risultati tecnologici simili o analoghi o - parlando di fotografia, p.e. - SUPERIORI (!), erano già stati conseguiti 30 anni fa, nel silenzio totale (o quasi) dei mass-media. Dunque perchè meravigliarsi tanto se oggi, AD 2005, riusciamo a far marciare un mini-semovente sulle sabbie di Marte quando, già più di 30 anni addietro, avevamo mandato una macchina (con tanto di Autista!) sulla Luna?!? Dov'è lo sviluppo tecnologico reale? Nel fatto che Marte è più lontano della Luna?!? Dov'è la "vera conquista"?...
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O-Mariner9-71-PIA02999_modest.jpgMars from Mariner 9: Ascraeus Lacus above the Martian Dust Storm128 visiteCaption NASA originale:"Oblique view of the crater complex near Ascraeus Lacus in the Tharsis region of Mars taken by Mariner 9. It is the northernmost of the prominent dark spots observed by Mariner during its approach to the Planet. The spot consists of several intersecting shallow crater-like depressions.
The main crater is approximately 21 Km (13 miles) across, the whole complex about 40 Km (25 miles) across.
The crater probably is in a relatively high area of the Martian surface, which accounts for its being visible above the dust storm.
The faint circular features outside the crater are probably atmospheric disturbances".
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O-Mariner9-71-PIA03100_modest.jpgMars from Mariner 9: Olympus Mons standing above the Martian Dust Storm (HR)119 visiteCaption NASA originale:"In pictures taken early in the Mariner 9 Mission, this region, shows a dark mountain standing above the Martian dust storm. This HR photograph shows that the area contains a complex crater, called Olympus Mons (Nix Olympica or Snows of Olympus), nearly 64 Km (40 miles) in diameter. The multiple crater form with scalloped margins, is characteristic of calderas - volcanic collapse depressions on Earth. In the Mariner 6 and 7 flights in 1969, an outer ring, 1600 Km (1.000 miles) in diameter, was seen. It is hidden by the dust in the oblique picture. Earth-based radar observations show that this is a high region on Mars and is usually covered by a white cloud when observed telescopically. This picture was taken on November 27, 1971".
Come potete vedere benissimo in questo frame - sebbene i contorni dell'immagine non sìano perfetti - la tecnica fotografica adottata per scattare fotografie della superficie di Marte da un'orbita stabile era già molto avanzata 34 anni fa. Oggi, grazie alle Sonde Mars Global Surveyor; 2001 - Mars Odyssey; Mars Express etc. riusciamo ad ottenere risultati fotografici sostanzialmente analoghi...
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O-Mariner9-72-Pollack_Crater_and_White-Rock.jpgPollack Crater and "White Rock" from Mariner 9 (RAW Frame - credits: NASA)53 visite"...It was interesting to browse through the Mariner 9 data set to locate these images, because evidently the Mariner 9 Team wasn't sure to make of these strange bright deposits.
The first one I posted was described as "white rock" in a comment on the image, and that name has stuck. But another image's descriptive comment read "curious ice patches".
Another totally misidentified not only the nature but the location of the photo, describing it as "Polar Cap".
Comments on images of other places in the Mariner 9 Catalog generally reflect the fact that Mars had not yet been systematically surveyed by an orbiter, so the scientists often weren't quite sure what they were looking at, and even when it was clear there were craters, those craters had mostly not yet been named.
I came across comments like "peculiar filametary structure" and "possible craters" and "streaky detail" and "cloud?" and "multitude of surface detail" and "odd fork-shaped bright pattern."
It's fun to browse through that table and imagine surveying Mars, with a spacecraft stationed at the Planet for the first time, made all the more dramatic by its initial obscuration by a dust storm that slowly cleared.
Mariner 9 is one of the more challenging data sets to work with because it's just so old. However, everything you need to access it, find images, view them, and convert them to more familiar formats is readily available online. First of all, the data itself can be found by browsing the data volumes at the PDS Imaging Node, and you can learn a little bit about the data at the National Space Science Data Center. To figure out what's what and to try to track down images of specific areas, you can download this spreadsheet (XLS format, zipped, 7.5 MB) containing an index to all the images.
The images are all in a format that won't be familiar to most of you, but like most spacecraft data you can convert a folder full of images to PNG format using my favorite amateur-produced software, Björn Jónsson's IMG2PNG. However, if you're only working with a couple of images, I'd recommend a different amateur-produced piece of software for converting the images, Piotr Masek's MarinerView, because MarinerView can be used to correct the Mariner 9 images (one at a time) for the little white specks of noise that are spattered across every one.
I'm slowly working on tracking down images of "White Rock" taken by every mission. First Mariner 9, then the Viking orbiters, then Mars Global Surveyor's MOC, then Mars Odyssey THEMIS, then Mars Express HRSC, and, finally, I should be able to produce Mars Reconnaissance Orbiter views from three different instruments: HiRISE, CTX, and CRISM. Stay tuned for further installments...".
Emily Lakdawalla (Planetary Society)MareKromium
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P-Mariner9-71-2-PIA02983.jpgMars from Mariner 9: a "Shield Volcano"196 visite(...o appena superiori) a quelli conseguiti dal Mariner 9. Tre decenni e mezzo - a nostro parere - del tutto sprecati. E non dimentichiamo i "colori": le Sonde Mariner e Viking ci hanno mandato svariate immagini in colori "veri" (cioè "così come li vedrebbero i nostri occhi se fossimo là"); oggi, grazie allo "sviluppo tecnologico", non c'è una foto di Marte che sia in "colori veri". Sono tutte quante in colori "approssimativamente" veri, e nessuno - NESSUNO! - ha ancora ben capito non solo che cosa significhi esattamente questa approssimazione, ma neppure quanto essa sia attendibile e verosimile...
Caption NASA originale:"A Martian "Shield Volcano" - approx.ly 25 miles across at the crater - photographed consecutively by Mariner 9 with the wide-angle and telephoto lenses. The summit crater and groves down the flank probably were produced by subsidence flowing subsurface movement of magma".
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